Why oxygen is needed for the combustion of a substance

Combustion is a violent reaction of substances to shine and heat, and accompanied by redox reactions, so an oxidizer is needed, and oxygen is an oxidant, in fact, combustion does not all need oxygen, chlorine is also an oxidant, chlorine and hydrogen can be burned together, and there are many similarities.

This is a theorem that does not need to be proved, a substance cannot be burned without oxygen.

Combustion is defined as a strong oxidizing reaction in which a substance emits light and heats. It is an oxidation reaction, and of course gas is required.

Combustion does not necessarily require oxygen, for example, magnesium (mg) can be burned in carbon dioxide (CO2).

Oxygen is not necessarily needed for combustion, and all vigorous oxidation reactions that emit light and heat are called combustion. Only the violent oxidation reaction defined in junior high school chemistry books as a luminous heat with the participation of oxygen is called combustion, because of the limitation of knowledge.

Oxygen doesn't necessarily need to burn! (The combustion of junior high school chemistry is a narrow sense of combustion, and oxygen must participate, and the combustion of high school and university is a real combustion, and oxygen is not necessarily involved).

Combustion is a violent chemical reaction phenomenon in which a substance emits light and exothermic. In general, a redox reaction occurs.

Not much to say about reactions with the participation of oxygen.

There is no oxygen to participate, and what can be seen in life, such as the combustion of fuel for rockets and missiles, which do not require oxygen. For example, Chang'e-1 is used"Long three"Sent to the sky, the combustion of the first stage rocket of the long three is is"Metamethylhydrazine", the accelerant is NO2, not oxygen.

Combustion is inherently defined on oxygen, and there is nothing to do. Just like the axioms in mathematics, they are based on universally accepted foundations. Your question is like asking 1+1=2.

Because the combustion of substances requires a natural substance, an oxidizer and a certain temperature.

For example, hydrogen + chlorine can be burned under ignition conditions.

Oxygen is an oxidizing agent, but it is not necessarily needed for combustion.

<> combustion reaction does not necessarily require oxygen. The three conditions for combustion are: combustibles; The temperature reaches the ignition point of the combustible; Accelerants.

At the junior high school level, the third condition may be written as the presence of air or oxygen. Air and oxygen are indeed the most common accelerants, but they are not the only ones, and other substances can also act as accelerants under certain conditions. Common accelerants include chlorine and potassium chlorate.

Wait. The equation for the combustion reaction.

1. Put the ignited magnesium strip into nitrogen, and the magnesium strip can still keep burning and react

3mg+n=mgn (condition is ignition).

This reaction does not require oxygen to participate. In addition, magnesium is also available in carbon dioxide.

Medium combustion: 2mg+co=2mgo+c (the condition is ignition) 2, the copper wire is burned in chlorine, producing a large amount of brown-yellow smoke, and a reaction occurs:

Cu+Cl=CuCl (condition is ignition).

In addition, alkali metals.

Iron, hydrogen, etc. can also be burned in chlorine, such as:

H+Cl=2HCl (condition is ignition).

2Fe + 3Cl = 2FeCl3 (condition is ignition).

1. Natural gas and oxygen ignition can produce carbon dioxide and water.

2. If oxygen is insufficient, carbon monoxide may also be generated.

3. If the oxygen is insufficient, carbon black may also be generated.

The essence of combustion is a redox reaction. Combustion does not necessarily require oxygen to participate, but needs to have an oxidant, and any luminous, heat, and violent redox reaction can be called combustion. In general, combustion requires the coexistence of three conditions to occur, namely, combustibles, oxidants, and temperatures to reach the ignition point.

Oxygen is the most common oxidizing agent in combustion reactions, but other compounds can also be oxidizing agents, such as magnesium, which can be burned in carbon dioxide, which is the oxidizing agent.

In the redox reaction, the oxidant undergoes a reduction reaction, and the corresponding product is a reduction product. It became a reducing product of the reaction.

1.When the ignited magnesium strips are placed in nitrogen, the magnesium strips can still remain burning, and a reaction occurs:

3mg+n=mgn (condition is ignition).

This reaction does not require oxygen to participate. In addition, magnesium can also be burned in carbon dioxide:

2mg+CO = 2mgo+c (condition is ignited)2The copper wire is burned in chlorine gas, producing a large amount of brownish-yellow smoke, which reacts:

Cu+Cl=CuCl (condition is ignition).

In addition, alkali metals, iron, hydrogen, etc. can also be burned in chlorine, such as:

H+Cl=2HCl (condition is ignition).

2Fe + 3Cl = 2FeCl3 (condition is ignition).

Generally speaking, there is oxygen in the gases produced when objects are burned (if they are burned with oxygen), such as carbon dioxide, carbon monoxide, sulfur dioxide, etc. If the product produced during combustion can no longer be burned, then this combustion is called complete combustion, and its product is called complete combustion product.

Such as CO2, SO2, H2O, P2O5, etc. are complete combustion products.